unicore32 core architecture: low level entry and setup codes

This patch implements low level entry and setup codes.

Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

1 files changed, 360 insertions, 0 deletions

diff --git a/arch/unicore32/kernel/setup.c b/arch/unicore32/kernel/setup.c
new file mode 100644
index 0000000000000..1e175a82844dc
--- /dev/null
+++ b/arch/unicore32/kernel/setup.c
@@ -0,0 +1,360 @@
+/*
+ * linux/arch/unicore32/kernel/setup.c
+ *
+ * Code specific to PKUnity SoC and UniCore ISA
+ *
+ * Copyright (C) 2001-2010 GUAN Xue-tao
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/stddef.h>
+#include <linux/ioport.h>
+#include <linux/delay.h>
+#include <linux/utsname.h>
+#include <linux/initrd.h>
+#include <linux/console.h>
+#include <linux/bootmem.h>
+#include <linux/seq_file.h>
+#include <linux/screen_info.h>
+#include <linux/init.h>
+#include <linux/root_dev.h>
+#include <linux/cpu.h>
+#include <linux/interrupt.h>
+#include <linux/smp.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/memblock.h>
+#include <linux/elf.h>
+#include <linux/io.h>
+
+#include <asm/cputype.h>
+#include <asm/sections.h>
+#include <asm/setup.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+#include <asm/traps.h>
+
+#include "setup.h"
+
+#ifndef MEM_SIZE
+#define MEM_SIZE	(16*1024*1024)
+#endif
+
+struct stack {
+	u32 irq[3];
+	u32 abt[3];
+	u32 und[3];
+} ____cacheline_aligned;
+
+static struct stack stacks[NR_CPUS];
+
+char elf_platform[ELF_PLATFORM_SIZE];
+EXPORT_SYMBOL(elf_platform);
+
+static char __initdata cmd_line[COMMAND_LINE_SIZE];
+
+static char default_command_line[COMMAND_LINE_SIZE] __initdata = CONFIG_CMDLINE;
+
+/*
+ * Standard memory resources
+ */
+static struct resource mem_res[] = {
+	{
+		.name = "Video RAM",
+		.start = 0,
+		.end = 0,
+		.flags = IORESOURCE_MEM
+	},
+	{
+		.name = "Kernel text",
+		.start = 0,
+		.end = 0,
+		.flags = IORESOURCE_MEM
+	},
+	{
+		.name = "Kernel data",
+		.start = 0,
+		.end = 0,
+		.flags = IORESOURCE_MEM
+	}
+};
+
+#define video_ram   mem_res[0]
+#define kernel_code mem_res[1]
+#define kernel_data mem_res[2]
+
+/*
+ * These functions re-use the assembly code in head.S, which
+ * already provide the required functionality.
+ */
+static void __init setup_processor(void)
+{
+	printk(KERN_DEFAULT "CPU: UniCore-II [%08x] revision %d, cr=%08lx\n",
+	       uc32_cpuid, (int)(uc32_cpuid >> 16) & 15, cr_alignment);
+
+	sprintf(init_utsname()->machine, "puv3");
+	sprintf(elf_platform, "ucv2");
+}
+
+/*
+ * cpu_init - initialise one CPU.
+ *
+ * cpu_init sets up the per-CPU stacks.
+ */
+void cpu_init(void)
+{
+	unsigned int cpu = smp_processor_id();
+	struct stack *stk = &stacks[cpu];
+
+	/*
+	 * setup stacks for re-entrant exception handlers
+	 */
+	__asm__ (
+	"mov.a	asr, %1\n\t"
+	"add	sp, %0, %2\n\t"
+	"mov.a	asr, %3\n\t"
+	"add	sp, %0, %4\n\t"
+	"mov.a	asr, %5\n\t"
+	"add	sp, %0, %6\n\t"
+	"mov.a	asr, %7"
+	    :
+	    : "r" (stk),
+	      "r" (PSR_R_BIT | PSR_I_BIT | INTR_MODE),
+	      "I" (offsetof(struct stack, irq[0])),
+	      "r" (PSR_R_BIT | PSR_I_BIT | ABRT_MODE),
+	      "I" (offsetof(struct stack, abt[0])),
+	      "r" (PSR_R_BIT | PSR_I_BIT | EXTN_MODE),
+	      "I" (offsetof(struct stack, und[0])),
+	      "r" (PSR_R_BIT | PSR_I_BIT | PRIV_MODE)
+	: "r30", "cc");
+}
+
+static int __init uc32_add_memory(unsigned long start, unsigned long size)
+{
+	struct membank *bank = &meminfo.bank[meminfo.nr_banks];
+
+	if (meminfo.nr_banks >= NR_BANKS) {
+		printk(KERN_CRIT "NR_BANKS too low, "
+			"ignoring memory at %#lx\n", start);
+		return -EINVAL;
+	}
+
+	/*
+	 * Ensure that start/size are aligned to a page boundary.
+	 * Size is appropriately rounded down, start is rounded up.
+	 */
+	size -= start & ~PAGE_MASK;
+
+	bank->start = PAGE_ALIGN(start);
+	bank->size  = size & PAGE_MASK;
+
+	/*
+	 * Check whether this memory region has non-zero size or
+	 * invalid node number.
+	 */
+	if (bank->size == 0)
+		return -EINVAL;
+
+	meminfo.nr_banks++;
+	return 0;
+}
+
+/*
+ * Pick out the memory size.  We look for mem=size@start,
+ * where start and size are "size[KkMm]"
+ */
+static int __init early_mem(char *p)
+{
+	static int usermem __initdata = 1;
+	unsigned long size, start;
+	char *endp;
+
+	/*
+	 * If the user specifies memory size, we
+	 * blow away any automatically generated
+	 * size.
+	 */
+	if (usermem) {
+		usermem = 0;
+		meminfo.nr_banks = 0;
+	}
+
+	start = PHYS_OFFSET;
+	size  = memparse(p, &endp);
+	if (*endp == '@')
+		start = memparse(endp + 1, NULL);
+
+	uc32_add_memory(start, size);
+
+	return 0;
+}
+early_param("mem", early_mem);
+
+static void __init
+request_standard_resources(struct meminfo *mi)
+{
+	struct resource *res;
+	int i;
+
+	kernel_code.start   = virt_to_phys(_stext);
+	kernel_code.end     = virt_to_phys(_etext - 1);
+	kernel_data.start   = virt_to_phys(_sdata);
+	kernel_data.end     = virt_to_phys(_end - 1);
+
+	for (i = 0; i < mi->nr_banks; i++) {
+		if (mi->bank[i].size == 0)
+			continue;
+
+		res = alloc_bootmem_low(sizeof(*res));
+		res->name  = "System RAM";
+		res->start = mi->bank[i].start;
+		res->end   = mi->bank[i].start + mi->bank[i].size - 1;
+		res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
+
+		request_resource(&iomem_resource, res);
+
+		if (kernel_code.start >= res->start &&
+		    kernel_code.end <= res->end)
+			request_resource(res, &kernel_code);
+		if (kernel_data.start >= res->start &&
+		    kernel_data.end <= res->end)
+			request_resource(res, &kernel_data);
+	}
+
+	video_ram.start = PKUNITY_UNIGFX_MMAP_BASE;
+	video_ram.end   = PKUNITY_UNIGFX_MMAP_BASE + PKUNITY_UNIGFX_MMAP_SIZE;
+	request_resource(&iomem_resource, &video_ram);
+}
+
+static void (*init_machine)(void) __initdata;
+
+static int __init customize_machine(void)
+{
+	/* customizes platform devices, or adds new ones */
+	if (init_machine)
+		init_machine();
+	return 0;
+}
+arch_initcall(customize_machine);
+
+void __init setup_arch(char **cmdline_p)
+{
+	char *from = default_command_line;
+
+	setup_processor();
+
+	init_mm.start_code = (unsigned long) _stext;
+	init_mm.end_code   = (unsigned long) _etext;
+	init_mm.end_data   = (unsigned long) _edata;
+	init_mm.brk	   = (unsigned long) _end;
+
+	/* parse_early_param needs a boot_command_line */
+	strlcpy(boot_command_line, from, COMMAND_LINE_SIZE);
+
+	/* populate cmd_line too for later use, preserving boot_command_line */
+	strlcpy(cmd_line, boot_command_line, COMMAND_LINE_SIZE);
+	*cmdline_p = cmd_line;
+
+	parse_early_param();
+
+	uc32_memblock_init(&meminfo);
+
+	paging_init();
+	request_standard_resources(&meminfo);
+
+	cpu_init();
+
+	/*
+	 * Set up various architecture-specific pointers
+	 */
+	init_machine = puv3_core_init;
+
+#ifdef CONFIG_VT
+#if defined(CONFIG_VGA_CONSOLE)
+	conswitchp = &vga_con;
+#elif defined(CONFIG_DUMMY_CONSOLE)
+	conswitchp = &dummy_con;
+#endif
+#endif
+	early_trap_init();
+}
+
+static struct cpu cpuinfo_unicore;
+
+static int __init topology_init(void)
+{
+	int i;
+
+	for_each_possible_cpu(i)
+		register_cpu(&cpuinfo_unicore, i);
+
+	return 0;
+}
+subsys_initcall(topology_init);
+
+#ifdef CONFIG_HAVE_PROC_CPU
+static int __init proc_cpu_init(void)
+{
+	struct proc_dir_entry *res;
+
+	res = proc_mkdir("cpu", NULL);
+	if (!res)
+		return -ENOMEM;
+	return 0;
+}
+fs_initcall(proc_cpu_init);
+#endif
+
+static int c_show(struct seq_file *m, void *v)
+{
+	seq_printf(m, "Processor\t: UniCore-II rev %d (%s)\n",
+		   (int)(uc32_cpuid >> 16) & 15, elf_platform);
+
+	seq_printf(m, "BogoMIPS\t: %lu.%02lu\n",
+		   loops_per_jiffy / (500000/HZ),
+		   (loops_per_jiffy / (5000/HZ)) % 100);
+
+	/* dump out the processor features */
+	seq_puts(m, "Features\t: CMOV UC-F64");
+
+	seq_printf(m, "\nCPU implementer\t: 0x%02x\n", uc32_cpuid >> 24);
+	seq_printf(m, "CPU architecture: 2\n");
+	seq_printf(m, "CPU revision\t: %d\n", (uc32_cpuid >> 16) & 15);
+
+	seq_printf(m, "Cache type\t: write-back\n"
+			"Cache clean\t: cp0 c5 ops\n"
+			"Cache lockdown\t: not support\n"
+			"Cache format\t: Harvard\n");
+
+	seq_puts(m, "\n");
+
+	seq_printf(m, "Hardware\t: PKUnity v3\n");
+
+	return 0;
+}
+
+static void *c_start(struct seq_file *m, loff_t *pos)
+{
+	return *pos < 1 ? (void *)1 : NULL;
+}
+
+static void *c_next(struct seq_file *m, void *v, loff_t *pos)
+{
+	++*pos;
+	return NULL;
+}
+
+static void c_stop(struct seq_file *m, void *v)
+{
+}
+
+const struct seq_operations cpuinfo_op = {
+	.start	= c_start,
+	.next	= c_next,
+	.stop	= c_stop,
+	.show	= c_show
+};